I made that mistake, when I made the first arduino board.
David Cuartielles took my first rectangular design , fixed a mistake (his first contribution) by applying the flying resistor you see.
and turned it into this
when I put some finishing touches I managed to get the spacing wrong...
We had 5 minutes before the deadline to go into production, the PCB guy was on the phone saying "send it now or it goes to next week" and we didn't have a name yet... they I said let's call it Arduino like a bar we used to go...there wasn't much time to think.
Then I'm fond of the mistake... it makes it not perfect therefore more human... Yes...it could have been all perfectly optimised... but if engineers ran the world it would be an unbearable place where to live 
Massimo